Gas-operated gun.



No. 885,166. PATENTED APR. 21, 1908.

W. MASON.

GAS OPERATED GUN. APPLIGATION FILED SEPT. 11, 1905.

7 SHEETS-SHEET 1.

PATENTED APR; 21, 1908.

7BHEETSSHEET 2.

W MASON GAS OPERATED GUN.

APPLICATION FILED SEPT 11, 1905 1 .2 v 1 i 11. 2 I I 1 No. 885,166. PATENTED APR. 21, 1908. W. MASON. GAS OPERATED GUN.

APPLICATION FILED SEPT. 11, 1905.

7 SHEETSSHEET 3.

PATENTED APR. 21, 1908.

W. MASON. GAS OPERATED GUN.

APPLICATION FILED SEPT. 11,1905.

7 SHEETS-SHEET 4. Y

No. 885,166. PATENTED APR. 21, 1908. W. MASON.

GAS OPERATED GUN.

APPLICATION FILED SEPT. 11, 1905.

7 SHEETS-SHEET 6.

PATENT'ED APR. 21, 1908.

SHEET 6.

'1 SHEETS- W MASON GAS OPBRATED GUN.

APPLICATION FILED SEPT. 11, 1905.

No. 885,166. PATENTED APR. 21, 1908. W. MASON.

GAS OPERATED GUN. APPLIOATIO H PILBDBEPT. 11, 1905. I 7 SHEETEsHEE-T R3,-4Q v WILLIAM MASON, OF NEW HAVEN,

ARMS 00., OF NEW HAVEN, CONNECTICUT, A CORPORATION.

CONNECTICUT, ASSIGNOR TO WINCHESTER REPEATING GAS-OPERATED GUN;

Specification of Letters Patent.

I-ate'nted April 21, 1908.

Application filed September 11, 1905. Serial No. 277,927.

T all whom it may concern:

Be it known that I, WILLIAM MASON, a citizen of the United States, residing at New Haven, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Gas-O erated Guns; and I do hereby declare the fo owing, when taken in connection with the accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in

Figure 1 a view in right hand elevation of a gun constructed in accordance with 111 invention, with the front end of its barre and the rear end of its butt-stock broken away. Fig. 2 a view in side elevation showing that portion of the barrel broken away from Fig. 1. Fig. 3 a plan view of what is shown in Fig. 1. Fig. 4 a broken view in left hand side elevation of the gun-frame to show the thumb-lever for operating the forearm look. Fig. 5 a broken view of the gun in vertical longitudinal section with its parts in their closed positions, the front end-of the barrel and the rear end of the butt-stock being broken away. Fig. 6 a sectional view to show as much of the barrel as is broken away in Fig. 5. Fig. 7 a broken view partly in elevation andpartly' in vertical longitudinal section drawn to natural size and showing the gun as open. Fig. 8 a brokenview in 7 side elevation showing the forward end of the guide-rod for the operating-spring. Fig. 9 a view partly in sideelevation and partly in vertical section showing the sliding gaschamber in itsopen position. Fig. 10 a view partly in vertical section and partly in elevation with particular reference to showing the forearm lock and the timing mechanism, the former being shown in its locked osition and the latter being shown as ready or firing the gun. Fig.- 11 a view of the same parts in horizontal section on the line ab of Fig. 10. Fig. 12 a view corresponding to Fig. 10 but showing the forearm mechanism unlocked and the timing mechanism performing its safety function. Fig. 13 a view corresponding to Fig. 11 but showing the parts in the positions illustrated in F1g. 12. Fig. 14 a detached viewin front elevation of the operatin -sp abutment. Fig. 15 a view thereo in si e elevation. Fig. 16 a view thereof in vertical longitudinal section. Fig.

17 a detached view in rear elevation of the forearm tip. Fig. 18 a view thereof in side elevation. Fig. 19 a view thereof in frontelevation. side elevation of the forearm heel. Fig.21 a view thereof in front elevation. Fig. 22 a detached view in rear elevation of the skeleton-bar. Fig. 23 a plan view thereof. Fig. 24 a view thereof in side elevation. Fig. 25 a plan view of the forearm locking bar. Fig. 26 a view thereof in inside elevation. Fig. 27 a view in side elevation of the forearm Fig. .20 a detached view in looking plunger. 7 Fig. 28 a reverse plan view thereof. Fig. 29 a detached view in side elevation of the forearm locking stud. Fig. 30 a view thereof in front elevation. Fig. 31 areverse plan view thereof. Fig. 32 a detached view in side elevation of the forearm locking dog. Fig. 33 a detached plan view of the forearm latch. Fig; 34 a view thereof in side elevation. Fig. 35 a detached view in side elevation of the bufler spring rod. Fig. 36 a similar view of the operating-spring guiderod. Fig. 37 a detac led edge view of the forearm looking or thumb-lever. Fig. 38 a view thereof in side elevation. Fig. 39 a reverse plan view thereof. Fig. 40 a detached plan view of the action slide. Fig. 41 a view thereof in right hand side elevation. Fig. 42 a detached view in side elevation of the breech-block. Fig. 43 a view thereof in front elevation. the rear breech-link. Fig. 45 a detached plan view of the front breech-link. Fig. 46 a plan view of the firing-pin striker. plan view of the firing-pin. Fig. 48 a plan view of the ejector. Fig. 49 a plan view of the breech-block pin. Fig. 50 a plan view of one of the ejector studs. Fig. 51 a detached plan view of the hammer-spring. Fig. 52 a detached view in inside elevation of one of the action-slide links; Fig. 53 an edge view thereof. Fig. 54 a detached plan view of the timing-lever. Fig. 55 a view thereof in side elevation. elevation of the timing-lever coupling piece. I My invention relates to an improvement in gas-operated guns of that class in which a portion of the gas developed by the explosion and burning of the powder is intercepted at the muzzle of the gun and utilized for the o eration of the breech-mechanism thereof, t.e object being to use the power so derived in the operation of toggle-link breech- Inechanism.

Fig. 44 a detached plan view of Fig. 47 a Fig. 56 a detached-view in side ve'snience and re p safetyand durability in use.

' chamber 2 'ha Further objects of my invention are "to: produce; a" gun "of the character described constructed' withlparticular reference to conability of operation and 1 With these ends' view, .my invention consists in .a gun having certain. details of construction and combinations of parts as will be hereinafter described and particularly recitedin the claims. f

In carrying out m invention as herein shown, I employ a' s 'ding sleeve-like asat its forward end a b etopening 3 locate inline with the bore of the gunbarre1 4, This chamber is formed near its forward end with lateral gas-escape holes 5 whichare left open or plugged up as may be required to propprly ga e the amount of gas intercepted at t e muzz e of the gun-barrel. Within the extreme forward end of the chamber, I locate a gas-check 6 having its rear end formed with a bevel 7 to coact with a corresponding bevel 8 at the extreme muzsupports and guides.

zle-end of the barrel to prevent the rearward movement of the intercepted gas until a sufficient pressure of gas has been accumulated in'the chamber to effect the operation of the breech-mechanism of the un. The said bevels also .coact to center t e bullet-hole 3 with respect to the bore of the gun-barrel 4.

As soon as the pressure .of gas'in the chamber is sufficient to start the same forward, and hence start the operation of. the breechmechanism, .the joint between the bevels 7 and 8 is broken when the'gasdmmediately finds its way rearward and relieves the pressure. It will be noticed that the gas-escape holes 5 are located back of the gas-check 6 though at the front end ofthe chamber. At its rear end the said chamber is formed with a correspondin ring of lateral cleaningholes 5 which provi e for the e'ection of the pewder'residue deposited by t e gas as well as for the escape of the gas as will be described later on. The said chamber 2 is also formed at its rear end with an internally threaded collar 9 adapting it to be screwed upon the slightly enlarged and threaded forward end of a sliding guide-sleeve 10 which extends rearward over the barrel 4 and corresponds in diameter to the gas-chamber 2 which it This construction ermits the chamber 2 to .be readily remove for being cleaned and for giving access to the muzzle end of the barrel for the same pur' pose. In this connection it may be said that one of the great defects of gas-operated guns as heretofore made has been the accumulation of powder residues on such of the moving parts as are exposed to the gas.

In order to prevent the chamber 2 from fouling b the accumulation in it of owder residues, locate upon the forward end of the barrel, a cleaning-sleeve 11' having a spiral rib 12, and secured to the barrel by a setcam es screw1'3. rib scrapes the-inner surfaces of the chamber, the dislodged material -be' blown b the ases back through the spiiid channel orme by the rib and ejectedthrough the cleaning-holes? aforesaid. The said rib 12 forms a bearing for the chamber 2 to ride back and-forth upon and the'spaces between the ribs provide, as it were, a recep. 'tacle for the residues that may not be carried rearward and away from the altogether b the gas. In the construction shown, the c amber 2 is slightly larger in diameter than the gun-barrel to permit the useof a sleeve 11 with its spiral rib 12. The s iral gas-escape channel formed by the s' 1r -rib 12 will,

cording to the pitch-of t e said rib, regulate the speed of. the escape of the gas caught and imprisoned by the gas-chamber and hence the s, ed of the forward movement of the gas- 0 amben Therefore by giving the rib 12 a predetermined pitch the action of the chamber 2' may be regulated as desired. Similarl the I sleeve 10 is kept from being fouled by a 0 caning-sleeve 14 secured in place upon the barrel by a screw 15 and furmshed w1th a series of parallel rings 16 virtually corres onding to the coils of the spiral rib 12 of the c caning-sleeve 11. The sleeve 10 is also made la er in diameter than the diameter of the arrel to provide a "space through which the gas may travel rearwardly so asto escape at the rear end of the" sleeve which bears upon the rings 16, the spaces between which provide areceptacle, as it were, for anyresidues which may not be carried away bythe as.

The motion derived from t a forward movement; of the chamber 2 and sleeve 10 is transmitted to the breech-mechanism by means of a connectin -rod 17 having its forward end fixed to theIower face of the guidesleeve 10 and having its rear end entered into,

a slot 18 inthe forward end of a skeleton-bar 19 which plays back and forth through an 0blon horizontal openin '20 in a tip 21 applied to t e forward end of t e chambered forearm 22, the said forearm tip 21 being provided with two .rearwardly extending arms 23 formed in their outer faces with screwholes 24 for the reception of screws by means of which the tip is secured in place and having their inner faces formed withgrooves 26 corresponding to the cross-sectional form of the side pieces of the skeleton-bar 19, whereby the said arms 23 constitute bearin s for the skeleton-bar as the same moves ack and forth. At its rear end the bar 19 is formed with a hole 27 for the reception of a bufferspring rod 28 constitutinga forward extension of the action-slide 29 which is formed at its forward end with a sleeve 30 in which the rear end of the said rod is pinned. The said rod 28 is encircled by a buffer-s ring 31 which is interposed between a shou der 32 at the rear end of the bar 19 and'the rear end of a head 33 located at the. forwardend of the rod and counterbored and threaded for the reception of the threaded, rear end of an operatingspring guide rod 34 extending forward through a hole 35 in the forearm tip 21, and having a head 36 slotted for the reception-of a screw-driver. The said rod 34 is encircled by an operating-spring 37 interposed between the said head 33 of the rod 28, and an operating-spring abutment 38 located within the forward end of the forearm and secured in place by four screws 39. This abutment has a clearance hole 40 through which the rod 34 moves back and forth and two cuts 41 which respectively receive and sup ort the side pieces of the skeleton-bar 1'9. hen the gun is fired and the gases intercepted in the chamber 2 begin to exert their forward pull, the buffer-spring 31 is sufficiently compressed to take off the shock of starting the operation of the breech-mechanism. Then, as the chamber 2 moves forward, the operating-spring 37 is compressed concurrently with the further compression of the buffer-spring. When the gas intercepted by the chamber 2 is released, the two springs expand and pull the chamber 2 back into its as-receiving position and at the same time c ose the breech-mechanism of the gun. It will thus be seen that I employ two springs, namely, the buffer-spring 31 and the operating-spring 37, whereas gas-operated guns have generally employed but one spring. In case but one spring is employed it must be made heavy enough not only to receive and store up the energy necessary to close the gun, butalso heavy enough to absorb the excess of energy produced by the violent 'movement of the gas-operated parts of the gun. The excess of energy thus stored in the spring above What is required for closing the gun, is given off by the spring, so to speak, in the form of shocks injurious to the gun. In guns of large calibers requiring proportionately la'rge operating springs, it will be seen that the shock to the gun produced by the excess of energy stored in the operating-spring is a serious drawback to the practical working of the gun. I avoid these objections by employing two springs as shown and described. The buffer-spring 31 receives all of the first shock of the forward movement of the gas chamber and is compressed thereby, but only to expand and harmlessly dissipate the energy so stored even during the opening of the gun. The operating-spring 37 may, therefore, be exactly proportioned to the work required of it in closing the gun without any shock to the moving parts thereof and without regard to the amount of energy generated by the exploding cartridge.

31 may be regarded as a regulating spring in so far as it overns or regulates the force employed. T erefore with two springs instead of one, I am enabled to secure a smooth, harerforate In one view, therefore, of my improved construction, the buffer-spring monious and balanced movement of the parts which conduce to safety in the working of the gun and to the durability of the gun.

The action slide 29 consists essentially of two parallel side bars having bearingin the opposite ends of a horizontal opening 42 in the orearm heel 43 which is secured in place by means of a screw passin through a screw hole 45 in an arm 46 exten ing forward into the forearm from the lower end of the heel. The rear ends of the two sidebars of the slide, are formed with forks 47 which receive the lower ends of two action-slide links 48. Link ins 49 passing thro'ugh the forks 47 and-the llnks 48 dpivotally secure the latter to the actionsli e. The upper ends of the said links 48 are provided wlth inwardly extending undercut coupling studs 50 which enter horizontal undercut slots 51 in the rear end of the rear breech-link 52 which swings upon a pin 53 passing throu h the gun-frame or receiver 54. At its rear en the said heel 43 is made with a bead or rib which projects beyond the adjacent surfaces of the forearm 22 and the gunframe or receiver 54 and forms a fender, as it were, for guarding the hand from being caught in the joint between the heel and the lower portion of the forward end of the gunperforated ears 55, 55, receiving between them'a perforated ear 56 located at the rear end of the front bwech-link 57, a pin 58 passing througlithe ears 55 and 56 pivotally connecting the links 52 and 57 together. The forward end of the front breech-link is formed withvtwo erforated ears 59, 59, receiving a d lug 60 at the rear end of the breech lock 61 which is pivotally connected with the link 57 by a pin 62 passing through the ears 59, 59, and the lug 60. The breechblock pin 62 has an arm or rib-extension 63 terminating in a finger 64 entering a notch 65 in the rear end of a guide-rib 66 on the right hand side of the block, the'said rib-extension 63 and rib 66 riding back and forth in a groove (not shown) in the right hand wall of the receiver, whereby the breech block is su ported and guided so far as its right hand sidia is concerned. The left hand end of the pin 62 is extended to form a squared head 68 entering a horizontal groove 69 in the inner face of the left hand side wall of the receiver 54 and supplementing the action of the rib 70 on the left hand side of the breech-block. The breech block is furnished with two extractors 71 and with a firing-pin 72 the rear end of which is struck by a firing-pin striker 73 mounted in the front breech link in position to have its rear end struck'by a hammer 74 which swings on a pin,75 in the gunframe 54.

The hammer 74 carries an antifriction roller 76 entering a groove-77 in the forward of the latter. I finger 97 is cleared from the rear end of the end of a hammer-spring which is Secured in the ower tang 79' which enters a long slot or openin in the lower portion of the gun-frame. hammer-buffer sprin 81 located uppn the hammer-spring 78 and s orter than t e same extends orward into position to be engagpd b the rear upper corner of the hammer w en t e same is automatically cocked. To reduce-the power required to open the gun by hand by taking off a good rtion of the pressure of the spring 78 from t e hammer 74, I employ a hammers ring depressor 82 secured y a pivot 83 to the rear breech-link 52 at a point very close to the pin 53 thereof and therefore at a point where the leverage thereof is very powerful even when the hnks are raised into nearly their full open positions when this depressor 82 acts to take off the pressure of the hammer-spring from the hammer.

The spent shells are extracted by two extractors 71 which draw them directly rearward after which they are ejected u ward through an opening 84 in the top of t e receiver 54, by thev finger 85 of a yoke-shaped ejector 86 the arms of which embrace the breech-block 61. At their rear ends the said arms are turned u ward and receive the ends of the threaded pms 87 of the ejector studs which extend through the receiver and are revented from working loose by means of ocking arms'88 located upon the outside of the receiver and engaged by spring pins 89 of familiar construction. The ejector is operated by the impingement against the forward edges of its upturned arms, of the rear end of the rib-extension 63 and the rear edge of the squared head 68.

The cocking-notch 90 of the hammer is entered by the forward end of a sear 91 which rocks upon the pin 92 of the trigger 93 under the control of a scar spring 94. In order to prevent the pulling of the trigger from operating the sear and releasing the hammer at any time other than when the gun is closed and locked, I employ timing- 'mechanism comprising a fly 95 constantly pushing downward by a s ring 96 and having a leaf-like finger 97 whic when it is swung forward between the trigger and the rear end of the sear, constitutes, as it were, a block by means of which the former lifts the rear end On the other hand when the sear, the pulling of the trigger is without The fly 95 is pivotally hung upon the hung upon a pin 99 supported in two arms 100 extending upward from the sides of the lower tang 79. A timing-lever spring 101 exerts a constant effort to swing the timinglever 98 so as to move its lower end forward and bring the finger 9.7 of its fly 95 into operating position between the trigger 93 and the rear end of the sear 91. The forward end of 78 the rear end of.

of the lever 98 wit right hand bar of the action-slide 29. This bar is formed, however, with what I may call .a' firing-notch 103 located so that when the the timing-lever is depressed with the effect of retracting its fly from such sition, bx the engagement of a l 102 at t e forwar end the lower edge of the slide is at the limit of its rearward movement,

which is when the gun is closed and looked,

the notch will register with the lug 102 which then rises 'into the notch and permits the ti -lever 98 to be swu by its s ring 101 and t e fly 95 to be move forwar between the trigger and the rear end of the sear.

For t e introduction of the first cartridge into the cartridge-chamber of'the gun-barrel 4, as Well as for the extraction of the cartridge in case of a misfire, it becomes necessary to manually open the gun for the operation of its breech-mechanism independently of the operation thereof by the pressure of gas intercepted at the muzzle of the gunbarrel. For such manual operation of the breech-mechanism, the forearm must be disconnected from the receiver 54 so that it may be worked back and forth for the operation of the action-slide which is connected with the rear breechlink as described, and hence with the other parts of the breech-mechanism. For the normal connection of the forearm with the receiver, I employ a forearmlatch 104 hung upon a pin 105 in a forearmlatch escutcheon 106 consisting of a long narrow plate set into a mortise 1.08 'in the lower face of the'rear end of the forearm 22 in which the escutcheon is secured by means of pins 109, the spring 110 of the latch 104 extending under the middle pin 109, whereby the latch is held in its locking position. The latch, which is formed with two locking hooks 111 and 112 and a tooth-like unlocking cam 113 which may be said to rise out of the center of the hook 1 12, coacts with a barlike locking-stud 1 14 having its rear end threaded for being screwed into the forward lower corner of the gun-frame 54 at a oint directly below a rectangular horizonta opening 115 formed therein for the passa e of the actionslide 29 the side bars of whic play back and forth in grooves 1 16 formed in the inner face of the side walls of-the receiver. At its for ward 'end the lower face of the stud 114 is formed with a notch 117 to receive the hook 112 of the latch 104, with a notch 118 to receive the hook 111 thereof, and with a longitudinal slot 119 leading out of the bottom of the notch 117 and adapted to receive the tooth-like: unlocking earn 113 of the latch 104. Normally the hooks 111 and 112 enter the notches 117 and 118 and lock the forearm to the receiver.

For the purpose of throwing the teeth of the latch out of the notches of the stud, I employ a rod-like unlocking plunger 120 exits forward end with an inclined notch 121 normall When, owever, the plun er .is moved forward the inclined rear wal of its notch 121 engages with the unlocking cam 113 and forces the latch 1'04 sufficiently downward to force the hooks 111 and 112 out of the notches 117 and 118', whereby .the forearm is disconnected from the receiver after which it may be manually moved forward for the manual operation of the breech-mechanism. The plunger 120 is locked in its forward position by means of a dog 122 rocking on a pin 123 and located in a slot 124 in the lower face of the rear end of the stud 114. When the forearm is started forward the lower wall of a square opening 125 formed in the heel 43 forthe reception of the stud 114, engages with the lower face 126 of the dog and throws the nose 127 thereof upward into a lockingnotch 128 in the lower face of the plunger 120, whereby the plunger is locked in its forward position in which it prevents the latch 104 from rengaging with the stud 114. On the other hand, just before the forearm reaches the limit of its rearward movement, the lower wall of the hole 125 engages with the lowerface 126 of the dog and swings the same on its pin 123, whereby its nose 127 is swung downward out of the locking-notch 128 whereby the plunger is thus released for bein drawn back into its unlocked osition in w ich it permits the hooks of the atch to enter the notches in the stud.

For the operation of the plunger 120, its rear end is formed with a head 129 grooved for the reception of the arms of a fork 130. turned inward from left to right from the forward end of a forearm locking-bar 131 located in a recess in the inner face of the left hand wall of the gun-frame. At its forward end the bar has a spring 133, both housed in a socket 134 in t e gun-frame and the spring exerting a constant effort to push the bar 131 rearward.

For the purpose of moving the bar 13 1 back and forth, as well as for moving its rear end inward and outward, I- employ a forearm locking-lever 135 havin a thumb-piece 135 and also having a threaded stud- 136 entering a threaded opening in the said left hand wall of the gun-frame, the oscillation of the lever being limited by two fixed pins 137 and 138 located out of line with each other and entering oppositely opening slots 1.39 and 140 formed in the inner face of the lever.

At its lower end the lever is formed with a 131 for forcing the rear end of the bar in- Ward. The wall 142 also coacts with a shoulder 146 on the head 145 for pushing the bar registered with the notch 117.

slide 29.

pin 132 encircled by a.

directly forward against the tension of the spring 133. On the other hand, the undercut wall 143 of the recess 141 coacts with the undercut 147 in the head 145 to draw the bar outward after it has been pushed rearward by the spring'133. Of course, if the sprin should fail to act, the beveled wall 143 an the undercut 147 would draw the bar rearward as wellas outward. The movement of the bar 131 back and forth accom anied by a corresponding movement of the p unger 120 for disconnecting the forearm from and recoupling it with the receiver.

The lateral movement of. the rear end of the bar 131 has a safety function and is de-" signed to move a beveled pin 1.48 projecting inwardly from the rear end of the bar, into and out of operative connection with the" 148 under the left hand edge of the rear end of the timing-lever 98 which atthis time is in its safety position with its rear end 'ele vated and its forward end depressed by the engagement of its safety nose 122 with the lower edge of the right hand bar of the action- The gun cannot now be filed until the lever 135 has been moved forward into its normal position, drawing the bar 131 rearward and also drawing the beveled pin 148 outward out of engagement with the timinglever 98 which is thus freed to swing onits pivot to bring the fly into operative posi tion as soon as the action-slide 29 is moved 7 into position to bring its firing-notch 103 into registration with the safety-nose 122 of the lever. It follows from this that if in the manual operation of the forearm, the same should be slammed back into its lockedposition which would bring the firing-notch 103 into position for releasing the lever 98 for the firing of the gun, the gun still could not be fired until after the lever 135 had been pushed forward for locking the forearm to the receiver, this forward movement of the lever retracting the beveled pin 148 from the timing-lever and so releasing the same. In other words, the operation of the locking-bar131 by the locking-lever 135 precludesthe possibility of the n with the forearm in its closed position, flit not positively locked to the gun-frame. If the gun should be fired with the forearm unlocked, it would, of course, be violently thrown forward. Therefore after the forearm has been unlocked from the gun-frame for the manual operation of' the gun for the purpose of loading the first cartridge into the gun-barrel or for the purpose of extracting .a misfire, the gun cannot be fired until the manual operation of forearm been drawn back to the limit of its rearward movement and the lever 135 has been pushed forward for relockmg the forearm to the n-frame. after wh ch the trigger xmafi l be pul e abutment 38' of the operating-spring 37 1s pendent of ,the barrel.

and is entirely inde- Therefore when the orearm is.disconnected from the receiver and em loyed for the operation of the actionslich; 29, the operating-spring Wlll move back and forth with the forearm without being compressed and so offer no reslstance whatever" to the manual operation of the gun which in fact is as easily operated manually as if its entire as 0 rating mech anism formed no part 0 it. his result could not be secured. 1f the'abutment 38 were carried by the barrel.

The magazine, which is of the box-type, may be of any approved construction and equipment. As herein shown it has a follower 149 elevated by a spring 150 secured to a .cover 151 with the forward end of which the forwardly inclined forward end wall 1.52 is made integral, the rear end wall 153 of the box-magazine being formed by the forward extension of the lower tang. At its forward end the cover 151 is formed with a lug 154 entering a groove 155 in the frame 54, while the rear end of the cover is en aged by a latch 156 hung on a pin 157 an controlled by a spring 158, this latch being located at the forward end of the finger-guard 159 which incloses the trigger, but the construction of the magazine and its adjuncts may be varied as desired. The breech-mechanism of the un herein shown and described is more fu lly illustrated and explained in my carried by the forearm prior patent No. 685,216 dated October 22,

1901, to which reference may be had.

It will be understood,- without further explanation, that after one cartrid e has been introduced into the gun-barrel, the action of a the gun is purely automatic beyond the pulling of the trigger.

In case of a misfit-e, the forearm may be uncoupled from the receiver to permit the unexploded shell to be removed from the gun.

It is apparent that in carrying out my invention some changes may be made in the construction herein shown and described. I would therefore have it understood that I do not limit myself thereto but hold myself at liberty to make such departures therefrom as fairly fall within the spirit and scope of' my invention.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is 1. In a gas-o. erated gun, the combination with the barre? and the breech-mechanism with the barre cameothereof, of a cleaning sleeve mounted upon the said barrel, a guide-sleeve concentric with the saidcleaning-sleeve and movable longitudinally over the same, a gas-chamber car ried' by the said guide-sleeve at the forward end thereof and formed at its forward end with a bullet-opening, and connection be-' tween the guide-sleeve and breech-mechanism.

2 :In a; as-o erated gun, the combination with the arre and the breech-mechanism thereof, of a lon 'tudinally movable sleevelike gas-chamber ocated at theImuzzle end of the barrel and having a bullet-openin a gascheck located within the forward en of the said chamber and coacting with the muzzle end of the barrel to confine the gases of explosion and to'center the said chamber and connection between the said chamber and breechsmechanism.

3. In a gas-operated gun, the combination and the breech-mechanism thereof, of a cleaning-sleeve mounted upon the said barrel and having an external spiral rib forming a spiral gas-esca e channel, a

uide-sleeve concentric with t e said cleanlug-sleeve and longitudinall movable over the same, a gas-chamber carried by the idesleeve at the forward en'dthereof, an con-' nectionbetween the guide-sleeve and breechmechanism, whereby a portion of the gas entering the as-chamber is allowed to escape rearward t ough the said spiral gas-escape channel.

4. In a gas-o erated gun, the combination with the barre and the breech-mechanism thereof, of a sleeve-like as-chamber located at the muzzle end of the arrel and formed at its forward end with gas-escape openings and at its rear end with cleaning openings through which the powder residues are forced by he escaping gas, and means connecting the said gas-chamber with the breechmechanism of the gun. I

5. In a gas-operated gun, the combination with the barre and the breech-mechanism thereof, of a sleeve-like gas-chamber located at the muzzle end of the barrel, and means located upon the exterior surface of the said end of the barrel for removing the powder residues from the walls of the said chamber, and connection between the said chamber and the breech-mechanism. 6. In agas-operated gun, the combination with the gun-barrel and the breech-mechanism thereof, of a sleeve-like gas chamber concentric withand pro'ecting beyond the muzzleend of the barrel, a guide-sleeve located u on the barrel and carrying the said gasc amber, means for cleaning the interior surfaces of the gas-chamber, the said means formin a passage for the rearward movement 0 the gas, a rece tacle for residues deposited thereby and a caring for the cham er, to reciprocate upon back and forth, and

connection between the said guide-sleeve and the breech-mechanism. I

7. In a gas-operated un, the combination with the gun-barrel an the breech-mechanism thereof, of a sleeve-like gas-chamber located at the muzzle end of the barrel, aguidesleeve located upon the barrel and carrying the said chamber, a cleaning rib ap lied to the barrel for cleaning the inner surfaces of thechamber, means applied to the barrel for cleaning the inner surfaces of the guide-sleeve, and connection between the sleeve and the breech-mechanism.

8. In a gas-operated gun, the combination with a gun-barrel, of a breech-mechanism, a sleeve-like gas-chamber concentric with and roj ecting beyond the muzzle-end of the gunbarrel, 9. guide-sleeve located upon the barrel and carrying the said gas-chamber, an operating-sprin for operating the breech-mechanism in c osin the gun, a rod extending rearward from t e said sleeve, a skeleton bar with which the said rod is connected, an action-slide connected with the said bar and the breech mechanism, a guide rod carried by the said slide, and operating and buffer springs V encircling the said rod.

9. In a gas-operated gun, the combination with the gun-barrel and the breech-mechanism thereof, of a sleeve-like gas-chamber 'located at the muzzle end of the barrel, connection between the said chamber and the breech-mechanism, including a rod, a skeleton-bar, an action-slide, a bufier-spring-rod connecting the skeleton-bar and action-slide, a buffer-spring encircling the said rod, a guide-rod mounted in the bufier-spring rod, an operating-spring encircling the said guiderod, and an abutment with which the said operating-spring coacts.

10. In' a gas-operated gun, the combination with the receiver thereof, of a forearm, means for couplin the forearm to the receiver and uncoup ing it therefrom to ermit the forearm to be used as a handle for the manual operation of the gun, a breechmechanism, means for utilizing a portion of the ases of explosion for o erating the breec -mechanism automaticall and connection between the said forearm and the breech-mechanism for the operation thereof manually when the forearm is uncoupled from the receiver.

11. In a as-o erated gun, the combination with a arre a forearm, and a breechmechanism, of a sleeve-like gas-chamber located at the muzzle end of the barrel, a forearm tip, a forearm heel, and connection between the said chamber and breech-mechanism including a skeleton-bar having bearing in the forearm tip, and an action-slide having bearihgin the forearm heel, the action-slide bein connected at its rear end with the breec -mechanism.

12. In a gas-operated gun, the combinabreech-mechanism including an operatingspring, and an abutment carried by the forearm and engaged by. the said spring, whereby when the forearm is disconnected from the gun-frame, the gun may be manually operated without compressing the operatingsprmg. 4 v

13." In a gas-o erated gun, the combination with a barre and a breech-mechanism, of a sleeve-like gas-chamber concentric with and projecting beyond the muzzle end of the barrel, and yieldin connection between the said chamber an breech-mechanism, including an operating-spring, and a bufferspring, the latter being brought into 0 eration as soon as the gun is fired and. the s eeve moved forward.

14. In a gas-o erated gum the combina-' a sleeve-like gas-chamber located at the muzzle end' of the barrel, and means controlled by the timing-mechanism for locking the forearm to and unlocking it from the gun-frame. Y 15. In a' gas-o erated un, the combination with a guname, a arrel, and breech and timing mechanisms, of a sleeve-like gas-chamber located at the muzzle end of the barrel, connection between the said chamber and the breech-mechanism, and means including a thumb-lever mounted in the frame for locking the forearm to and unlocking it from the frame.

16. In a gas-operated gun, the combination with a frame, a barrel, a forearm, a breech mechanism, a timing-mechanism, and

a forearm locking mechanism, of a sleevelike gas-chamber located at the muzzle end of the barrel and connected with the breechmechanism, and means for locking the forearm to and unlocking it from the frame including a lever mounted in the frame, and a bar connected at its rear end with the timingmechanism and having its forward end connected with the forearmlocking mechanism.

'17; In a gas-operated gun, the combination with a frame, a barrel, a forearm, and breech and a timing-mechanisms, of a gasoperated mechanism located at the muzzle end of the barrel, connection between the saidmechanism and the breech-mechanism, and a forearm-locking mechanism controlled by the timing-mechanism and including a forearm-latch, a stud mounted in the frame and coacting with the said latch, a plunger located in the said stud, a bar connected mounted in the frame and :co'acting with the rear end of the said bar for the operation thereof and with the timlngmiechamsm.

18. In *a gas-operated the" combiner tion with the frame or-recelver thereof, of a forearm and a forearm heel mounted in the rear end'of the'forearman'd formed with a rib or bead rejectingbeyond the forearm and the gun-game and forming a fender for the joint between the heel and the frame.

19'. Ina gaseoperated gun, the combinationwiththebar rel and the breech-mechcontrol,

longitudinally over them 'for having its interior surfaces cleaned thereby, a gas tween the said guide-sleeve and the breech mechanism, the said forward cleaning-sleeve providing a channel for the escape, under of the 'gas'rearward from the gaschamber.

In testimony whereof, I have signed this specification in the presence of two subscribing witnesses. 4

' WILLIAM MASON.

Witnesses:

CLARA L. WEED, GEORGE, D. SEYMOUR. 

